High-density three-dimensional multilayer memory and fabrication method

Abstract

The present disclosure provides a high-density three-dimensional multilayer memory and a fabrication method, and relates to the preparation technology of memories. The memory comprises an underlying circuit part and a basic structure body disposed above the underlying circuit part, wherein the basic structure body is divided into two independent interdigitated structures by a curve-shaped division groove, at least three memory cell holes are formed in the curve-shaped division groove side by side, a vertical electrode is disposed in each memory cell hole, and the memory medium is an insulating medium; and a buffer region is placed on the inner wall of the memory cell hole and at the position of a first conducting medium layer, the buffer region protrudes from the inner wall of the memory cell hole to the central axis of the memory cell hole, and the buffer region is connected to the memory medium.

What is claimed is: 
     
         1 . A high-density three-dimensional multilayer memory, comprising an underlying circuit part and a basic structure body disposed above the underlying circuit part, wherein the basic structure body is divided into two independent interdigitated structures, referred to as a first interdigitated structure and a second interdigitated structure respectively, by a curve-shaped division groove, the basic structure body comprises first conducting medium layers and insulating medium layers alternately stacked on top of each other from bottom to top, at least three memory cell holes are formed in the curve-shaped division groove side by side, a vertical electrode is disposed in each memory cell hole, and an insulating isolation pillar is disposed between every two adjacent memory cell holes;
 the vertical electrode, the first conducting medium layer of the interdigitated structure, and the memory medium between the vertical electrode and the first conducting medium layer form a memory structure;   the memory can be a PN junction type semiconductor memory or a Schottky semiconductor memory;   the memory medium is an insulating medium; and   a buffer region is placed on an inner wall of the memory cell hole and at a position of the first conducting medium layer, the buffer region protrudes from the inner wall of the memory cell hole to a central axis of the memory cell hole, and the buffer region is connected to the memory medium.   
     
     
         2 . The high-density three-dimensional multilayer memory according to  claim 1 , wherein a contour line of the side wall of the memory cell hole on a longitudinal section is a straight line. 
     
     
         3 . The high-density three-dimensional multilayer memory according to  claim 1 , wherein the vertical electrode is in an electrical connection with the underlying circuit part. 
     
     
         4 . The high-density three-dimensional multilayer memory according to  claim 1 , wherein:
 the first conducting medium is made of a P-type semiconductor, and the vertical electrode is made of an N-type semiconductor, wherein the buffer region is made of a semiconductor material with a doping type same as that of the first conducting medium and a doping concentration that is lower than that of the first conducting medium;   or, the first conducting medium layer is an N-type semiconductor, and the vertical electrode is made of a P-type semiconductor, wherein the buffer region is made of a semiconductor material of which the doping type is the same as that of the first conducting medium and the doping concentration is lower than that of the first conducting medium;   or, the first conducting medium layer is made of a semiconductor material meeting a requirement of a Schottky diode, and the vertical electrode is made of a metal meeting the requirement of the Schottky diode, wherein the buffer region is made of a semiconductor material of which the doping type is the same as that of the first conducting medium and the doping concentration is lower than that of the first conducting medium.   
     
     
         5 . The high-density three-dimensional multilayer memory according to  claim 1 , wherein the memory can be a resistance change memory, a magnetic phase change memory, a phase change memory or a ferroelectric memory.